You do have to have the FE written complete and passed, within the last 2 years, regardless of employment... before you interview. But that's it beforehand.

The sim is the frist day of the interview process, pass or fail. If you pass you get to come back for lots-o-fun! Next is an HR interview and a situational based interview, where you act as a captain with a crew of 3 and have some sort of, well... situation. It is to show leadership, CRM, and stuff like that. Then after lunch, you get to feel stupid and do a bunch of computer tests, kinda like soemthing you'd get on a military officer qual test.

Try aviationinterviews.com for some info.